In the process of drilling and completing oil wells, it has been common practice to place heavy steel casing in a well and to place cement between the casing and the well to anchor the casing in place and prevent migration of fluids outside the casing. After an upper portion of a well has been drilled and cased, it is common to continue drilling the well and to line a lower portion of the well with a liner lowered through the upper cased portion of the well. Liner hangers have been used to mechanically support the upper end of the liner from the lower end of the previously set casing and to seal the liner to the casing. Liner hangers have included slips for mechanical support and packers for forming a seal.
More recently, expandable liner hangers, such as those sold under the trademark VERSAFLEX by Halliburton Energy Services, have been developed. Expandable liner hangers provide both mechanical support and a fluid seal by use of a number of elastomeric rings carried on a section of expandable tubing. After the liner hanger is properly positioned in a cased portion of a well, an expansion cone may be forced through the liner hanger to expand the liner hanger expanding the elastomeric seals into contact with the casing to provide both mechanical support and a fluid seal.